I don't mind Karlach, though she's not my personal favorite; The one thing that does bother me is when their background doesn't match up with their power level. Gale is one of the most powerful knowledgeable wizards! Who starts at level 1 for some reason. Karlach is a veteran of the blood war! A level one veteran. I know they try to handwave it away with "Uh ummm the worm depowers them" but honestly it just seems dumb to me. Just write a more appropriate history for a level 1 character, is it that hard?
The only thing that is good about Karlach is her voice actor.
And I agree 100% on the power level disconnect from the story.
How about Jaheira? She should be one of the most powerful druids in the realms, fully decked out with artefact-level gear, yet she can get 2 shot during harper battle (and drop mundane gear, not even magical, lol), btw she has no tadpole in her. And we can find a scroll in her room with a ritual that allows ARCHDRUIDS to extend their lifespan. She’s also keeping Belm there, instead of taking it with her on a dangerous mission.
If we are starting at level one, there is no need for larger than life backstories, like blood war veterans or mages who fcked the gods (literally). There are ways to develop characters from scratch as the game goes on. And if we are meeting returning characters, it should be a huge deal, not just another dude to level up and gear up with leftovers from your camp supply chest…